arXiv 0809.28522008-09astro-phgr-qchep-phhep-th

Cosmology With Non-Minimally Coupled K-Field

A. A. Sen, N. Chandrachani Devi

备注：: 10 pages, Revtex style, 14 eps figures, to appear in General Relativity and Gravitation
DOI：: 10.1007/s10714-009-0882-y

英文摘要：

We consider non-minimally coupled (with gravity) scalar field with non-canonical kinetic energy. The form of the kinetic term is of Dirac-Born-Infeld (DBI) form.We study the early evolution of the universe when it is sourced only by the k-field, as well as late time evolution when both the matter and k-field are present. For the k-field, we have considered constant potential as well as potential inspired from Boundary String Field Theory (B-SFT). We show that it is possible to have inflationary solution in early time as well as late time accelerating phase. The solutions also exhibit attractor property in a sense that it does not depend on the initial conditions for a certain values of the parameters.

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